Centos 下同时安装 Mysql4 和 Mysql5，二进制方式
Centos 下同时安装 Mysql4 和 Mysql5，二进制方式
系统中原有 Mysql4 ，但是需要使用 Mysql5 的一些新特性，但是 Mysql4 又不能够删除，所以需要同时安装两个版本的 Mysql。
为此，用测试机进行了实验，安装下面两个版本的 Mysql。 mysql-standard-4.1.15-pc-linux-gnu-i686-glibc23.tar.gz mysql-5.0.86-linux-i686.tar.gz
步骤如下：
1、首先安装 Mysql4
tar –xvzf mysql-standard-4.1.15-pc-linux-gnu-i686-glibc23.tar.gz cp -rf mysql-standard-4.1.15-pc-linux-gnu-i686-glibc23.tar.gz /usr/local/mysql4 groupadd mysql4 useradd -n mysql4 -c "" -g mysql4 -d /nonexistent -s /usr/sbin/nologin cd /usr/local/mysql4 chown –R mysql4 chgrp –R mysql4 ./scripts/mysql_install_db --user=mysql4
chown –R root . chown –R mysql4 data ./bin/mysqld_safe --user=mysql4 &
这样，mysql4 就安装完成了，可以通过 ./bin/mysql –uroot 进入查看，并且通过 status 可以看到数据库的状态：
mysql> status -------------- ./bin/mysql Ver 14.7 Distrib 4.1.15, for pc-linux-gnu (i686) using readline 4.3 Connection id: 2 Current database: Current user: root@localhost SSL: Not in use Current pager: stdout Using outfile: '' Using delimiter: ; Server version: 4.1.15-standard Protocol version: 10 Connection: Localhost via UNIX socket Server characterset: latin1 Db characterset: latin1 Client characterset: latin1 Conn. characterset: latin1 UNIX socket: /tmp/mysql.sock Uptime: 2 min 32 sec Threads: 1 Questions: 5 Slow queries: 0 Opens: 11 Flush tables: 1 Open tables: 5 Queries per second avg: 0.033 -------------- 如果需要加入到系统自启动中，则可以进行如下的操作。
cp support-files/mysql.server /etc/rc.d/init.d/mysql4.server
接下来需要对这个文件中的一些变量进行修改
basedir=/usr/local/mysql4
datadir=/usr/local/mysql4/data
pid_file=/var/run/mysql4/mysql4.pid
拷贝一个配置文件到 data 目录下 cp /usr/local/mysql4/support-files/my-xxxx.cnf /usr/local/mysql4/data/my.cnf
修改 my.cnf 文件
[mysqld] user = mysql4 port = 3306 socket = /tmp/mysql4.sock
最后，建立运行时的目录
mkdir /var/run/mysql4 chown -R mysql4:mysql4 /var/run/mysql4/
ln -s /etc/init.d/mysql4.server /etc/rc3.d/S90mysql4 ln -s /etc/init.d/mysql4.server /etc/rc3.d/K91mysql4
这样，系统启动后 mysql4 的服务就会自动起来了。
2、安装 Mysql 5
mysql5 的安装和 mysql4 差不多，只是 mysql4 的部分修改为 mysql5。
groupadd mysql5 useradd –n mysql5 –c “” –g mysql5 –d /noexistent –s /usr/sbin/nologin chown –R mysql5 . chgrp –R mysql5 . ./scripts/mysql_install_db --user=mysql5 chown –R root . chown –R mysql5 data cp support-files/mysql.server /etc/rc.d/init.d/mysql5.server 修改文件中的变量 basedir=/usr/local/mysql5 datadir=/usr/local/mysql5/data pid_file=/var/run/mysql5/mysql5.pid server_pid_file=/var/run/mysql5/mysql5.pid user=mysql5 拷贝一个配置文件 cp support-files/my-medium.cnf my.cnf 修改配置文件中的变量
user = mysql5 port = 3307 socket = /tmp/mysql5.sock
最后建立文件夹
mkdir /var/run/mysql5 chown -R mysql5:mysql5 /var/run/mysql5/
启动服务 /etc/rc.d/init.d/mysql5.server start 查看服务的状态
[root@fltrpsrv2 mysql5]# /usr/local/mysql5/bin/mysql -uroot -S/tmp/mysql5.sock Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.0.86-log MySQL Community Server (GPL) Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> status -------------- /usr/local/mysql5/bin/mysql Ver 14.12 Distrib 5.0.86, for pc-linux-gnu (i686) using readline 5.1 Connection id: 1 Current database: Current user: root@localhost SSL: Not in use Current pager: stdout Using outfile: '' Using delimiter: ; Server version: 5.0.86-log MySQL Community Server (GPL) Protocol version: 10 Connection: Localhost via UNIX socket Server characterset: latin1 Db characterset: latin1 Client characterset: latin1 Conn. characterset: latin1 UNIX socket: /tmp/mysql5.sock Uptime: 28 sec Threads: 1 Questions: 4 Slow queries: 0 Opens: 11 Flush tables: 1 Open tables: 6 Queries per second avg: 0.143 --------------
可以看到 mysql5 已经安装成功了 加入系统自启动
ln -s /etc/init.d/mysql5.server /etc/rc3.d/S90mysql5
ln -s /etc/init.d/mysql5.server /etc/rc3.d/K91mysql5
参考资料： 1、Install Mysql4 and Mysql5 on a single FreeBSD 6.2 Server 2、Install Mysql from tar.gz Packages on Other Unix-Like Systems